design-systems: add 74 brand DESIGN.md files (VoltAgent/awesome-design-md)

- 74 brands: airbnb, stripe, apple, figma, linear, vercel, etc.
- 147 files: DESIGN.md + README.md per brand (~2.1 MB)
- Each DESIGN.md contains structured brand analysis (colors, typography, components)
- Updated 00-overview.md with new design-systems directory

concepts/customer-journey-mapping.md

@@ -0,0 +1,63 @@
+---
+title: Customer Journey Mapping
+description: Designing for each stage of the user's decision process.
+tags: [journey, mapping, UX, conversion, funnel]
+---
+
+# Customer Journey Mapping
+
+## 6 Stages of Customer Journey
+
+### 1. Awareness
+- **Goal:** Capture attention
+- **Design:** Hero with bold statement
+- **Metrics:** Time on page, scroll depth
+
+### 2. Interest
+- **Goal:** Engage with content
+- **Design:** Problem metrics, social proof
+- **Metrics:** Scroll depth, section engagement
+
+### 3. Consideration
+- **Goal:** Evaluate solution
+- **Design:** Feature comparison, pricing
+- **Metrics:** Pricing page views, CTA clicks
+
+### 4. Evaluation
+- **Goal:** Build trust
+- **Design:** Testimonials, case studies
+- **Metrics:** Trust signal clicks, form fills
+
+### 5. Decision
+- **Goal:** Convert
+- **Design:** CTA above the fold, guarantee
+- **Metrics:** Conversion rate, form submissions
+
+### 6. Retention
+- **Goal:** Keep engaged
+- **Design:** Onboarding, newsletter signup
+- **Metrics:** Activation rate, engagement
+
+## Landing Page Journey Flow
+
+```
+Hero (Awareness)
+  ↓
+Problem (Interest)
+  ↓
+Solution (Consideration)
+  ↓
+Features (Evaluation)
+  ↓
+Social Proof (Trust)
+  ↓
+Pricing (Decision)
+  ↓
+CTA (Conversion)
+```
+
+## Anti-Patterns
+- Don't put pricing before social proof
+- Don't ask for too much information upfront
+- Don't hide CTA below the fold
+- Don't skip mobile experience